Conventionally known is a storage medium drive unit having a slot for insertion of a platelike storage medium having a semiconductor memory and a plurality of terminal electrodes, wherein when the storage medium is inserted into the slot and mounted in a storage medium mounting portion provided inside the slot, data reading and/or writing from/to the storage medium is performed. At present, various storage media having different sizes are provided as the platelike storage medium.
Some of these storage media have common terminal electrodes so that they can be inserted into the slot of the same storage medium drive unit for data reading and/or writing. However, these storage media having common terminal electrodes yet have different sizes, that is, they are different in length, width, and thickness. As means for using the slot commonly for the storage media different in size, an adapter is mounted to the storage medium having a smaller size to allow the insertion of this storage medium into the slot, thus allowing the use of any storage media having common terminal electrodes.
In this case where the adapter is used to allow the common use of the slot for the storage media having different sizes, however, there is a problem that every time the storage medium having a smaller size is inserted into the slot to perform data reading and/or writing, the adapter must be mounted to this storage medium, so that the usability is reduced.
As another means for using the slot commonly for the storage media different in size, it is consider to fix connection terminals adapted to be connected to the terminal electrodes of each storage medium inside the slot, provide a plurality of guides respectively corresponding to the storage media having different sizes inside the slot, detect the storage medium inserted into the slot, and select a suitable one of the guides according to the result of this detection. However, this means requires a complicated mechanism to result in an increase in manufacturing cost of the storage medium drive unit.
It is accordingly an object of the present invention to provide a storage medium loading mechanism and a storage medium drive unit which can ensure simplification of the mechanism and can improve the usability.